The invention described in this patent was made by an employee of the United States Government and may be manufactured and used by or for the Government for governmental purposes without the payment of any royalties.
1. Field of the Invention
In general, this invention pertains to imaging systems or telescopes. Specifically, this invention pertains to Fourier imaging systems or telescopes.
2. Background Information
The theory and capability of Fourier telescopes is well understood. See J. W. Campbell, Imaging the Sun in Hard X-Rays Using Fourier Telescopes, NASA Technical Memorandum, NASA TM-08390 (January 1993). However, the cost of a Fourier telescope based on a traditional design can be prohibitive because of the expense associated with the physical production of a single grid pair and the need for numerous grid pairs (e.g., 48 grids were used in a basic telescope design in Campbell, NASA TM-108390 at 109). While single and double grid pair Fourier telescopes have been theorized (see J. W. Campbell, A Single Grid Pair Fourier Telescope for Imaging the Sky in Hard X-rays and Gamma Rays, 2808 SPIE Proc. 546 (1996)), a device for implementing such telescopes has never been created. In addition, this single grid pair theory only contemplated the collection of data at discrete, predetermined points in the available spectrum.
This invention has the ability to create Fourier-based images with only two grid pairs. (Use of one grid pair is also possible with this invention.) The two grid pairs are manipulated in a manner that allows (1) a first grid pair to provide multiple real components of the Fourier-based image and (2) a second grid pair to provide multiple imaginary components of the Fourier-based image. The novelty of this invention resides in the use of only two grid pairs to provide the same imaging information that has been traditionally collected with multiple grid pairs. Additional novelty resides in the fact that this invention has the ability to image continuously across the available spectrum.
An object of this invention is to provide a Fourier-based system for imaging atomic particles (e.g., neutrons) and electromagnetic radiation (e.g., gamma rays, x-rays).
Another object of this invention is to provide a Fourier-based system for imaging atomic particles and electromagnetic radiation with one grid pair.
A further object of this invention is to provide a Fourier-based system for imaging atomic particles and electromagnetic radiation with two grid pairs.
A still further object of this invention is to provide a Fourier-based system for imaging atomic particles and electromagnetic radiation capable of imaging over the entire available spectrum rather than imaging at discrete, predetermined intervals in the spectrum.